Thanks. I already knew most of the stuff covered in the article (or at least I thought I did :-), but it got me started down the right path. It turns out I needed to tweak my connection string. Once I did that, the errors went away.

But I still don't understand why this works, or why what I had before didn't. If providerName="System.Data.Odbc", shouldn't I just be able to specify a data source I've set up in the ODBC Admin applet?

I guess there's a good reason why there are entire articles and Web sites devoted to connection strings. Is there some documentation on how to construct a connection string? (Not connectionstrings.com -- I'm looking for something like a list of keywords, dependencies
on the underlying driver, etc.)